Ask DACS, July 2014

Q – I have a PowerPC Macintosh that is new to me but is obviously not a new machine. It boots and runs just fine on OS X 10.5. It also has Mac OS 9.2 installed in another partition, so I set it to boot OS 9.2 and it hangs as soon as the desktop is displayed. With the machine frozen, how can I switch back to OS X? [This was my own question, not from the audience.]

A – Richard Corzo, Apple SIG leader and our resident Mac expert, said to hold down the Option key when the machine first starts to boot. It will pause and display all of the boot options available; you can then change the boot location and let the boot process resume. When I tried this the next day, it worked.

Q – I have seen references to what seems to be a new Wi-Fi standard called “802.11 AC”. Does anyone know how this is different from the “Wireless N” standard or others? Is this backward compatible with past standards?

A – At the meeting the consensus was that the AC standard is backward compatible with N, G and other standards. According to the WikiPedia article, this is not correct. The article states that AC operates on the 5GHz band only, whereas 802.11N can operate in both the 2.4GHz and 5GHz bands. The older standards also operate on single bands: 802.11A is 5GHz only and 802.11G is 2.4GHz only. In simplistic terms, the AC standard offers faster speeds over shorter range by using a wider frequency channel (80MHz or 160MHz) versus the 40MHz channel width used by high-speed N and 20MHz used by the earlier A, B, and G Wi-Fi standards. For a new AC Wi-Fi router/access point to be compatible with your existing devices, those devices must operate on the 5GHz frequency band using a protocol supported by the router. Caveat emptor! Read the specifications of any new device carefully to be sure it is compatible with your existing equipment. Once you open the box, it may be too late! In my discussion I have used the word ‘channel’ to mean the amount of spectrum used for a working connection between the Wi-Fi access point and your device (laptop, tablet, or phone). This is not necessarily the same meaning used by the FCC or device manufacturers. If you want to learn more, start reading with the basic Wi-Fi article at wikipedia.org/wiki/WiFi and then follow links to the many, many articles on related topics.

Q – When using public Wi-Fi, is there a good free program to use to increase your security?

A – Certainly when using any public Wi-Fi, your computer should be running a good firewall that has as close to zero ports open as possible. As we discussed this, we determined that the question was really about using a virtual private network (VPN) to encrypt data going to and from your computer. A VPN is a technique that creates an encrypted “tunnel” over the public Internet between your computer and a remote end point. The Wikipedia article is wikipedia.org/wiki/Vpn. Many enterprises require employees who work from home to use a VPN to communicate with the company network. All information on the Internet is carried in packets. Normally this data is sent “in the clear”, so when using a public Wi-Fi connection, your emails (for example) are transmitted as plain text that can be captured and read by anyone on the same Wi-Fi who has with the required software. A VPN uses one of several encryption techniques to encode all data between your computer and the VPN end point. This “hides” your data from anyone snooping on that open Wi-Fi or anywhere else between your computer and the VPN end point. The end point of an enterprise VPN would be inside the company network firewall, thus keeping company information secure.

This same VPN technology is used by citizens of repressive nations like China, Saudi Arabia and Iran to “tunnel” past the censored Internet normally available in those nations. This allows them to reach the so-called free and uncensored Internet available to the rest of the world. Citizens inside such countries rely on volunteers on the outside to set up end points, also called proxy servers, which receive the encrypted packets, decrypt the data and pass it on to the intended destination such as a website. When the website responds, the process is reversed. The IP address recorded by the website is the address of the proxy, not the actual address of the user’s computer. Anonymizer and Tor (anonymity network) are two examples. The Tor network was in the news recently as the only method to reach the Silk Road website where it is alleged all sorts of illegal commodities could be purchased using Bitcoin. Further research is left to the reader. A member suggested a PC Magazine article on this topic that reviews nine free VPN services and the client software.

Q – Are there free services that will host a small website?

A – The free hosting service on Yahoo, called Geocities, was closed years ago. Apparently Google offers something called “Google Sites” as a free service. I have used Register4Less.com as my domain registrar for many years. They offer limited free web hosting as part of the domain registration service. I’ve never used it but your friend could use that for the cost of transferring his domain to Register4Less which would be one year of registration or $15. I’ve run websites from servers in my basement for many, many years. When I first started, I used a “dynamic DNS” service to point my domain name to the ever-changing IP address on my router. This worked surprisingly well even on the lowest speed Charter cable Internet service. Searching for “free website hosting” returned a lot of hits. Caveat emptor! Watch out if they ask for a credit card. A small site may be free until you get some traffic and then the costs for data traffic can escalate very fast.

DACS News

Your Board of Directors would like to announce some exciting changes to DACS. We have found an opportunity that will allow us to continue providing monthly meetings with speakers on technical topics … [Read More...]

By Mike Kaltschnee, Co-Director, Danbury Hackerspace.
We’re excited to help DACS continue, but in a different form. When I was 19 I was a regular at Computer Ease, a local computer store, and one … [Read More...]

Have you ever wondered who the other members of DACS are, what their interests are, and whether they have experience and knowledge that could benefit you? Would you like to be able to identify and … [Read More...]

Join DACS Meetup!

Follow Us

Ask DACS Disclaimer

Ask DACS is a Question and Answer session before the main presentation at the monthly General Meeting. We solicit questions from the floor and then answers from other audience members. My role as moderator is to try to guide the discussion to a likely solution to the problem. The answers include my own post-meeting research.

DACS offers no warranty as to the correctness of the answers and anyone following these suggestions or answers does so at their own risk. In other words, we could be totally wrong!